[LifeIsGood]

Falling on sword and admitting right up front I switched the cables when installing the battery [pause for well-deserved abuse].

Naturally the ignition did not work and immediately realized my mistake. Installed correctly but still no ignition. Accessories are working but nothing when turning key.

- checked inline fuses at battery and have voltage on both sides.
- tried resetting circuit breaker on engine block
- checked fuse at key
+ continuity across terminals
+ no voltage on incoming wire

No obvious other fuses. Is there a fuse box? Any other thoughts?

Any suggestions appreciated and abuse expected.....

[GregT]

Hmmm, you've already checked everything I would check. I do have a fuse to the key power, so double check that one. You reset the circuit breaker on the engine.

Did you smell anything burning or see any puffs of smoke when it happened? perhaps a power wire burned up somewhere? Should be getting power to the key for the start signal. Maybe replace that fuse with a new one?

[LifeIsGood]

Thanks for the reply. No smoke or smells…just some sparks at the terminals.
Been spending time trying to follow the wiring but much of it is wrapped or goes out of sight.
Does anyone know the general wiring route (e.g. battery->key->starter with circuit breaker on engine in the mix)?

[GregT]

Can't help you much on wiring either. I have been trying to trace wires in my boat also and it is very difficult because someone added a bunch of red power wires that disappear into the dash - very difficult to identify what they power.

I know a bunch of the engine wiring goes into a wrapped look from the dash to the rear, and I found a power wire from my fuse box to the key switch, but once it comes out of the switch it goes into the loom to the engine.

Check for power at the connection coming to your switch first. If you can, check down by the starter also and see if there is a circuit breaker there or possibly burned wires.

[Sparks&Stripes]

Go to the mercury marine website and launch the parts catalog. You can search by “stern drive” then your engine and serial number. It will bring up exploded diagrams so you can look at the engine wiring to see what components you have. Every boat is different. If you have a battery on off switch I would check that first, check the kill switch (tether), and make sure it’s in neutral. There is a 90a fuse normally that is located on the starter that could be blown.

[LifeIsGood]

That site was helpful but I did not see a wiring diagram for the ignition system.

I am not getting a voltage reading on the wire coming to the breaker at the key. Would like to know what is between the battery and the key.

[Sparks&Stripes]

You’re just going to have to look at the terminals on the switch and trace the power wire coming in. One terminal will be the main power coming in, one will be accessory if the key turns to the left, one will be power on, and the last will be start which will send power to the starter solenoid to crank over. My power coming in to my switch is a larger gauge red wire compared to the other 3. However, your Mariah is a sea fox so I’m not sure if they did their wiring different than how the original Mariah boats were. I don’t know exactly know where the ignition power comes from on your boat but it should just be battery positive in so I’d check the battery disconnect. I will attach the standard marine wire colors photo.

[GregT]

Originally Posted by LifeIsGood

That site was helpful but I did not see a wiring diagram for the ignition system.

I am not getting a voltage reading on the wire coming to the breaker at the key. Would like to know what is between the battery and the key.

You are talking about the fused red wire coming to the key I believe. You need power on that wire o activate the start/run circuit. If you have no power there and the fuse is definitely good, then the power loss is back in the engine area. Double check the circuit breaker on top of the engine and check for power in and out there. I believe that feeds the system, so if it isn't resetting then that is the problem. If it is reset, double check the wires down at the starter.

Also check the battery connections, sometimes they put wires directly to the battery, like bilge pump and trim pump, maybe you missed putting back on the power wire for the key circuit if it had one?

[LifeIsGood]

Again, appreciate the replies… This is helpful. Definitely no power coming into fuse before the key and didn’t appear to be getting any power on the two leads coming into the circuit breaker on the engine block so the problem seems to be between the battery and that circuit breaker, many of the wires are wrapped in tape and or otherwise covered so it has been difficult to follow the wire .

[LifeIsGood]

Yes, the 50 amp circuit breaker on the engine block has no power coming to it and it is between the battery and the key and the problem must be between the circuit breaker and the battery. Any ideas on what components other than straight wiring are between the battery and the circuit breaker?